Left atrial appendage occluder for improving sealing effect and manufacturing method thereof

ABSTRACT

A left atrial appendage occluder for improving sealing effect and a manufacturing method thereof are provided. The left atrial appendage occluder includes a sealing portion and an anchoring portion coupled to the sealing portion. The sealing portion and the anchoring portion abut against each other. A tight connection between the sealing portion and the anchoring portion can be achieved by applying a pre-tightening force, such that the left atrial appendage occluder can be better attached to and occlude the left atrial appendage after being release.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a continuation of PCT Application No.PCT/CN2018/087552, filed on May 18, 2018, which claims priority toChinese Patent Application No. 201710369080.1, filed on May 23, 2017,the disclosures of which are hereby incorporated by reference in theirentireties.

TECHNICAL FIELD

The present disclosure relates to the field of medical instruments, andin particular to an interventional treatment instrument for occluding aleft atrial appendage (LAA) and a manufacturing method thereof.

BACKGROUND

Atrial fibrillation (AF) is the most common persistent arrhythmia. Theincidence of AF increases with age and is up to 10% in people over 75years old. When AF occurs, the atrial pulsation rate is up to 300-600beats per minute. The heart rate is often fast and irregular, and aneffective atrial systolic function is lost. In case of AF, thecontractility of a left atrial appendage (LAA) is decreased; inaddition, morphological characteristics of the LAA and the uneventrabecula in the LAA which make the blood flow generate an eddy in theLAA and the blood flow rate slow down, thus resulting in the formationof thrombus. For patients with nonvalvular AF, more than 90% of leftatrium thrombi occur in the LAA, and after the thrombi fall off, thethrombi will enter the cerebral arterial blood vessels through theaorta, thereby causing cerebral embolism, namely stroke.

Currently, to prevent AF patients from the risk of stroke, preventivetreatments are clinically performed by mainly utilizing the followingthree methods: anticoagulant treatment, surgical treatment, andpercutaneous left atrial appendage occlusion (LAAO) treatment. Theanticoagulant treatment is to restrain blood coagulation by oralanticoagulants, so as to reduce the risk of thrombus formation in theLAA, and then reduce the occurrence probability of stoke. Clinic trialsshow that the anticoagulant treatment can remarkably reduce theoccurrence probability of stroke, but the anticoagulant treatment is along-term process and also has remarkable complications, mainlyincluding bleeding complications, and even may lead to severe cases. Thesurgical treatment includes surgical ablation or suture of LAA. However,surgical trauma is large, and such surgery is generally performed duringthe valve replacement surgery or the coronary artery bypass graftsurgery. Patients, especially elderly patients, generally are hard toaccept a simple LAA surgery. The percutaneous LAAO treatment is todeliver and then release a LAA occluder to the LAA disposed in the rightatrium of the heart by utilizing a delivery sheath with a smallerdiameter in a percutaneous puncture mode. The LAA occluder can occludethe orifice of the LAA to prevent blood flow in the atrium from enteringthe LAA, thereby preventing thrombus formation and achieving a purposeof preventing AF-induced thromboembolism. Since 2001, the percutaneousLAAO treatment has been in use, and has successively subject to animalexperiments and clinical trials. Based on the clinical trials, the LAAOtreatment can effectively reduce the occurrence probability of stroke ofthe AF patients.

The LAA occluder currently in the market mainly has two types ofstructures: a plug structure and a double-disc structure.

Because the application time of the LAA occluder is relatively short,the technology is relatively immature, there will be some complicationsafter surgery and affect the living quality of the patient. Among them,residual shunt of an instrument is one of the main complications of LAAocclusion. In the case of the LAA occluder with the plug structure, 8%of patients had residual shunt complications from their 6-monthfollow-up results, and 32% to 34.5% of patients in different centers hadsome degrees of residual shunt complications from their 12-monthfollow-up results. In the case of the LAA occluder with the double-discstructure, 2%-16.2% of patients in different centers had moderateresidual shunt complications from their 12-month follow-up results. Theincidence of residual shunt complications is high, which will affect theliving quality of patients. Therefore, reducing the residual shunt afterLAA occlusion is one of the main goals of improving the clinicalapplication value of the LAA occluder.

The LAA occluder with the double-disc structure usually includes asealing portion and an anchoring portion. After the LAA occluder isreleased, the sealing portion occludes the orifice of the LAA, and theanchoring portion is released inside the LAA and is provided with barbsto fix the sealing portion. After being released, the sealing portion ofthe LAA occluder should be closely attached to the orifice of the LAA toocclude the LAA. If the sealing portion fails to be closely attached tothe orifice of the LAA and the sealing portion may be suspended in theleft atrium, resulting that a sufficient occlusion effect for theorifice of the LAA cannot be achieved, and the risk of thrombosis may befurther increased. A major factor that causes the sealing portion to beineffectively attached to the LAA is related to the connection betweenthe sealing portion and the anchoring portion. That is, the anchoringportion and the sealing portion fail to be tightly connected together,the overall length of the occluder is relatively longer, and theanchoring portion is radially compressed, further increasing the overalllength of LAA occlude after being released, and also causing an increasein the axial distance between the sealing portion and the anchoringportion, such that the sealing portion cannot be effectively attached tothe LAA after being released, resulting in residual shunts.

SUMMARY

A left atrial appendage occluder is provided, which advances aconnection manner between a sealing portion and an anchoring portion,thereby avoiding and inhibiting an axial elongation of the left atrialappendage occluder as a whole, and further ensuring that the sealingportion is attached to and occludes the left atrial appendage.

A left atrial appendage occluder for improving sealing effect includes asealing portion and an anchoring portion coupled to the sealing portion.The sealing portion and the anchoring portion are in mutual abutment.

It is noted that the mutual abutment between the sealing portion and theanchoring portion refers to that at least a part of the sealing portionand at least a part of the anchoring portion are in contact with eachother, and the sealing portion is deformed due to an abutment force.

According to the present disclosure, a tight connection between thesealing portion and the anchoring portion can be achieved by applying apre-tightening force. After being released, the left atrial appendageoccluder can be better attached to and occlude the left atrialappendage, and even if one of the anchoring portion and the sealingportion is radially compressed to lengthen, the sealing portion can bekept in contact with the anchoring portion to ensure the sealing effect.

The left atrial appendage occluder according to the present disclosureis capable of effectively improving the sealing performance and reducingresidual shunts.

In combination with the related art, one or more layers of flow blockingmembrane are disposed inside the sealing portion. A periphery of theanchoring portion can also be coated with a flow blocking membrane, forexample, all or part of an outer surface of the anchoring portion iscoated with the flow blocking membrane.

Unless otherwise stated, shapes and positional relationships herein aredescribed based on a state in which the left atrial appendage occluderis released and expanded in a body, and the state may also be referredto be a released state or an expanded state. Before being released, theleft atrial appendage occluder is compressed within a delivery device tobe in a state which may be referred to be a compressed state or apre-release state.

In an embodiment, the sealing portion and the anchoring portionseparately and independently have a wire frame structure or amesh-shaped structure.

The sealing portion and the anchoring portion can be processed byweaving or cutting, individually. The sealing portion (or the anchoringportion) can be in a regular or irregular wire frame structure. Thesealing portion in the wire frame structure may be provided with aframework, as required, at a suitable position in the wire framestructure to increase a strength, and the framework may have a largercross-sectional area or have at least a greater strength with respect toother portions of the sealing portion. The sealing portion in thenetwork-shaped structure may include regular or irregular cells, and inan implementation, the network-shaped structure includes diamond-shapedcells or substantially diamond-shaped cells. The network-shapedstructure is at least radially compressible to facilitate retraction andrelease. The mesh-shaped structure explicitly appears a warp and weftstructure, and longitudinal parts and latitudinal parts of themesh-shaped structure intersect with each other via nodes in a fixedmanner. In an implementation, the longitudinal parts and the latitudinalparts of the mesh-shaped structure intersect with each other in anon-fixed manner, that is, the longitudinal parts and the latitudinalparts can be slidably moved with respect to each other in anintersecting manner, thereby providing a capability of compliance anddeformation.

In an embodiment, the sealing portion is a sealing disc or a sealingplug.

It is noted that the term “disc” or “plug” is used to represent ageneral shape. For example, the term “disc” represents a structure in aflat shape with an outer edge, and the outer edge is in a shape, such asa circular shape or other shapes according to actual requirements,substantially fitted with features of anatomical structures of the leftatrial appendage.

For example, the term “plug” is used to represent a structure in acolumn shape with a certain thickness, such as an approximate cylinderand cone. However, a shape of an outer circumference or a generatrix ofthe sealing portion is not strictly limited, and can be definedreferring to the related art on one hand and the actual requirements onthe other hand. The shape of the sealing portion itself is not criticalto the present disclosure. But of course, the present disclosureprovides a preferred or improved solution for the sealing portion.

In an embodiment, the sealing portion is a sealing disc. The sealingportion is provided with a presetting state and an abutting state. Inthe presetting state, the sealing portion is free from contact with theanchoring portion. In the abutting state, the sealing portion is incontact with the anchoring portion. A middle part of a disc bottom ofthe sealing portion in the abutting state is deformed facing axiallytoward the anchoring portion with respect to the presetting state.

In an embodiment, the middle part of the disc bottom of the sealingportion in the abutting state is provided with a deformation protrudingaxially toward the anchoring portion with respect to the presettingstate.

In an embodiment, the sealing portion includes a disc surface facingaway from the anchoring portion, a disc bottom facing the anchoringportion, and an intermediate part connecting the disc surface and thedisc bottom. The disc bottom is planar, or a middle part of the discbottom protrudes toward the anchoring portion, or the middle part of thedisc bottom protrudes away from the anchoring portion.

The disc surface, the disc bottom, and the intermediate part integrallyform a cage-shaped structure. One or more flow blocking membranes may bedisposed inside the cage-shaped structure. Parts of the cage-shapedstructure other than necessary hollow parts may be closed or partiallyopen. When weaving and processing the sealing portion, one convergingend may be formed at each of the disc bottom and the disc surface.

Since the cage-shaped structure has a certain space inside, the sealingeffect can be ensured even if there is a certain deformation in thecage-shaped structure. According to the present disclosure, thecage-shaped structure is particularly suitable for achieving a tightabutment against the anchoring portion.

A diameter of the cage-shaped structure mainly includes a diameter ofthe intermediate part, a diameter of the anchoring portion, and adiameter of the disc surface. The diameter of the intermediate part issubstantially equal to the diameter of the anchoring portion. Thediameter of the disc surface is slightly larger than the diameter of theintermediate part, so as to improve the sealing effect of an end of thesealing portion.

In an embodiment, the sealing portion is provided with a presettingstate and an abutting state. In the presetting state, the sealingportion is free from contact with the anchoring portion. In the abuttingstate, the sealing portion is in contact with the anchoring portion. Adiameter of the disc bottom in the presetting state is larger than adiameter of the disc bottom in the abutting state.

The disc surface or the disc bottom described herein may be in anapproximately circular shape. If the disc surface or the disc bottom isin other shapes, it may be appreciated that a cross-sectional area or anoverall thickness of the disc bottom in the presetting state is largerthan that of the disc bottom in the abutting state. Taking the discsurface and the disc bottom in a circular shape as an example, since adiameter of the disc surface is larger than a diameter of the discbottom, the sealing portion is in a truncated cone shape as a whole. Thesealing portion is progressively converged as it goes toward a bottomend thereof, such that a top surface of an upper end of the sealingportion is slightly larger, and a bottom surface of the bottom end ofthe sealing portion is slightly smaller. In this way, when the sealingportion is in contact with the anchoring portion, the sealing portioncan be conformed to be attached with the anchoring portion.

In an implementation, the sealing portion is provided with a presettingstate and an abutting state. In the presetting state, the sealingportion is free from contact with the anchoring portion. In the abuttingstate, the sealing portion is in contact with the anchoring portion. Atleast one of the intermediate part and the disc bottom of the sealingportion in the abutting state has a deformation with respect to thepresetting state.

The presetting state refers to a state in which a shape of the sealingportion after being processed but before assembling the left atrialappendage occluder or subjecting the sealing portion to an externalforce. After assembly, since the sealing portion is in abutment againstthe anchoring portion, and in order to increase or maintain thepre-tightening force between the sealing portion and the anchoringportion, the sealing portion is deformed after being abutted against theanchoring portion.

In an embodiment, the intermediate part of the sealing portion in theabutting state has a radially contracted deformation with respect to thepresetting state.

When the sealing portion and the anchoring portion are moved away fromeach other or subjected to a radially compression, the radiallycontracted deformation can offset or delay a tendency of an axialelongation of the left atrial appendage occluder to ensure a sealing foran opening portion of the left atrial appendage. The radially contracteddeformation allows the intermediate part to have a certain taper and tobetter fit the left atrial appendage, so as to improve the sealingeffect.

In an embodiment, the disc bottom of the sealing portion in the abuttingstate is provided with a deformation protruding axially toward theanchoring portion with respect to the presetting state.

Based on a similar principle, the deformation protruding axially towardthe anchoring portion can also offset or delay the axial elongation as awhole. The abutment between the sealing portion and the anchoringportion is substantially maintained to ensure the sealing effect.

In an embodiment, the sealing portion abuts against the anchoringportion at least at an outer edge of the disc bottom. The outer edge ofthe disc bottom is abutted against the anchoring portion, and a greaterdeformation of the sealing portion can be obtained under a samepre-tightening force, which is more favorable for compensating andoffsetting the axial elongation.

In an embodiment, connection parts of the sealing portion and theanchoring portion are connected in a staggered manner.

In an embodiment, the sealing portion and the anchoring portion areconstricted and converged respectively, and the sealing portion and theanchoring portion are connected together via a connector.

In the present disclosure, wire strands of the sealing portion and theanchoring portion can be connection parts formed by shape convergence.The connection parts of the sealing portion and the anchoring portionextend toward each other and are fixed in a staggered manner.

However, the connection parts formed by shape convergence are notlimited to be formed in a converged manner. In the related art, theconnection parts of the sealing portion and the sealing portion aregenerally aligned with each other, and end surfaces of the connectionparts are directly abutted against each other when the connection partsare directly connected. Of course, a transitional connector can also beadopted, but this structure will lead to an excessive overall axiallength of the left atrial appendage occluder, which is disadvantageousfor sealing.

In the present disclosure, the connection parts of the sealing portionand the anchoring portion are connected in a staggered manner, such thatthe connection parts can extend toward each other without spatiallyinterference, a distance between the sealing portion and the sealingportion can be greatly reduced, and the sealing effect can be improved.

In an embodiment, both of the sealing portion 1100 and the anchoringportion 1200 are integrated with or fixed to their connection partrespectively.

The sealing portion and the anchoring portion may be integrated withtheir respective connection parts after a laser cutting or weavingprocess. Alternatively, the connection parts are independent members andare fixed with sealing portion and the anchoring portion respectively bywelding or the like. In an implementation, the sealing portion and theanchoring portion are integrated with their respective connection parts,thereby facilitating processing and ensuring overall strength.

In an embodiment, the above-mentioned shape convergence is a globalconvergence or a local convergence.

As the sealing portion and the anchoring portion are used to occlude theleft atrial appendage, parts of the sealing portion and the anchoringportion have various diameters ranged within a certain size range, whilediameters of the connection parts are smaller. Thus the transition indiameter between a main body of the sealing portion and the connectionpart of the sealing portion, and a transition in diameter between a mainbody of the anchoring portion and the connection part of anchoringportion, are gradual or abrupt. For example, when the connection partsare converged in a manner of global convergence, a portion with a varieddiameter is in a tapered structure. The local convergence can beconsidered as an abrupt change in diameter, for example, a portion witha larger cross-sectional area abruptly changes into a rod or a strandwith a smaller cross-sectional area.

In an embodiment, each of the sealing portion and the anchoring portionhas one connection part connected with the other. Alternatively, each ofthe sealing portion and the anchoring portion has multiple connectionparts, and the multiple connection parts of the sealing portion areconnected with the multiple connection parts of the anchoring portion ina one-to-one correspondence.

The number and positions of the connection parts are not strictlylimited. In a case that each of the sealing portion and the anchoringportion has only one connection part, the connection part is generallyarranged in a middle of the sealing portion or the anchoring portion.

In an embodiment, the connection parts of the sealing portion andanchoring portion are directly connected or connected via a connector.

When the connection parts are directly connected, that is, theconnection parts of the sealing portion and anchoring portion are incontact with each other, and are fixed to each other by welding,hooping, intertwining, and the like. When the connection parts areconnected via a connector, that is, the connection parts may be freefrom contact with each other, but are respectively fixed with theconnector, and the connector may be a single component or an assembly ofmultiple components.

In an embodiment, each of the connection parts of the sealing portionand the anchoring portion extends along a straight line.

Alternatively, one of the connection parts extends along a straight lineand the other of the connection parts extends along a curve line.

Alternatively, each of the connection parts of the sealing portion andthe anchoring portion extends along a curve line.

The sealing portion and the anchoring portion are arranged oppositely,and the connection parts of the sealing portion and the anchoringportion extend toward and are connected with each other, and the pathsalong which the connection parts extend are not strictly restrictedduring an extending process. In order to simplify the structure, in animplementation, each of the connection parts of the sealing portion andthe anchoring portion extends along a straight line.

The connection part itself may be either a simple straight rod or arelatively complicated three-dimensional structure, and thus extendingalong a straight line herein should be understood as an overall trend,that is, the extending process does not involve with a circuitous orbending shape as a whole.

Further, in an embodiment, the connection parts of the sealing portionand the anchoring portion both extend along an axial of the left atrialappendage occluder.

In an embodiment, the connection parts of the sealing portion and theanchoring portion are nested within or offset with each other at aposition in which the sealing portion and the anchoring portioncooperate with each other.

Since the connection parts of the sealing portion and the anchoringportion are arranged in a staggered manner, the connection parts canextend to be staggered with each other in a mutually nested manner or ina mutually offset manner without spatial interference. A mutually offsetmanner is defined with respect to the mutually nested manner, and shouldnot be understood as being far away from each other. For example, in across section perpendicular to the axial of the left atrial appendageoccluder, the connection parts of the sealing portion and the anchoringportion may be attached to each other or have a certain gaptherebetween.

In an embodiment, the connection parts of the sealing portion and theanchoring portion extend toward each other, and each of the connectionparts extends beyond a terminal end of the other connection part.

When one connection part extends beyond the terminal end of the otherconnection part, it also means that the terminal end of the otherconnection part extends beyond a terminal end of the one connectionpart. In this way, the connection parts have projections, in a directionperpendicular to the axial of the left atrial appendage occluder,arranged side by side or at least partially overlap with each other at aposition in which the connection parts of the sealing portion and theanchoring portion cooperate with each other.

When one of the sealing portion and the anchoring portion is nestedwithin the other, the projections of the sealing portion and theanchoring portion must overlap. When the sealing portion and theanchoring portion are offset with each other, the shapes of theprojections of the sealing portion and the anchoring portion are relatedto a projection direction, and it is possible that the projections ofthe sealing portion and the anchoring portion are arranged side by sideor partially overlap with each other. When the sealing portion and theanchoring portion are offset with each other and one of the sealingportion and the anchoring portion does not extend beyond a terminal endof the other, the sealing portion and the anchoring portion can befurther moved toward each other and the structure of the left atrialappendage occluder is not compact enough.

In the case that the sealing portion and the anchoring portion each havemesh-shaped structures, wires for weaving the sealing portion and theanchoring portion are bundled individually and further connected witheach other via a connector. Structure features is formed by bundling thewires, corresponding steps in the processing are included in the processof bundling, and that is, multiple wires are converged and bundled intoone strand.

In the case that the sealing portion and the anchoring portion each havewire frame structures, the sealing portion or the anchoring portion isgenerally formed by cutting a pipe, and an end terminal of the pipe canbe considered as a converging part.

In an embodiment, the sealing portion includes a bottom part facing theanchoring portion, and the bottom part of the sealing portion includes afirst converging part. A middle part of the anchoring portion in aradial direction includes a second converging part. The first convergingpart and the second converging part extend toward each other and aremisaligned.

Pulling the first converging and the second converging toward theconnector in opposite directions may cause the main bodies of thesealing portion and the anchoring portion to be moved close to and untiltightly abutted against each other. The first converging and the secondconverging are pulled through separate channels, thereby avoidinginterference and facilitating assembly.

In an embodiment, the first converging part and the second convergingpart are arranged side-by-side in a staggered manner or are arranged ina nesting inside and outside in a staggered manner. In general, twochannels are arranged offset from each other, thereby further avoidinginterference during pulling the first converging part and the secondconverging part and facilitating assembly.

In an embodiment, the anchoring portion extends from the connector awayfrom the sealing portion to form an extending portion. One side of theextending portion facing away from the connector is bent outward andturns back to the bottom part of the sealing portion to form aturning-back portion. The turning-back portion is abutted against thebottom part of the sealing portion.

The anchoring portion is an outward bent structure as a whole. Theturning-back portion extends around a periphery of the extendingportion, such that the turning-back portion and the extending portiontogether form a double-layer structure. A certain space is definedinside the double-layer structure, which can accommodate and allow adeformation of the anchoring portion, after the anchoring portion istightly abutted against the sealing portion, without weakening theanchoring effect.

In an embodiment, the anchoring portion extends from the connector awayfrom the sealing portion to form an extending portion. One side of theextending portion facing away from the connector is bent outward andturns back to the bottom part of the sealing portion to form aturning-back portion. The turning-back portion bends inward and isconstricted at the bottom part of the sealing portion to form a neckedopening portion. The necked opening portion abuts against the bottompart of the sealing portion.

The turning-back portion bends inward and is constricted at the bottompart of the sealing portion to form the necked opening portion, and thenecked opening portion abuts against the bottom part of the sealingportion.

The necked opening portion extends inward substantially and radially tobe in surface contact with the bottom part of the sealing portion,thereby facilitating applying a pre-tightening force. Although theanchoring portion and the sealing portion are in hollow structures, thesurface contact herein can be understood as an abutment betweenmesh-shaped surfaces, and it is not necessary to be limited to a surfacecontact between solid bodies.

In an embodiment, the first converging part is disposed at a center ofthe bottom part of the sealing portion. The necked opening portionextends upward to abut against an outer edge of the bottom part of thesealing portion. In this way, the bottom part of the sealing portion isformed into an inverted cone shape under the action of thepre-tightening force.

In an embodiment, the necked opening portion is suspended above aperiphery of the extending portion or connected to the extendingportion. When the necked opening portion is suspended above theperiphery of the extending portion, that is, the necked opening portionand the periphery of the extending portion are not connected or onlyslightly contact with each other, and are freely movable relative toeach other when deformed. When the necked opening portion is connectedto the extending portion with one of a fixed connection, a slidingconnection, and a rotation fit, a relative movement between the neckedopening portion and extending portion is restrained in some extent.

In an embodiment, the extending portion is in a tapered shape, and anend of the extending portion having a larger diameter is disposed awayfrom the connector and is provided with an opening.

The extending portion is in a horn-shaped structure, therebyfacilitating retraction and improving strength and structural stabilityat a flared end (that is, the end of the extending portion provided withthe opening).

In an embodiment, the anchoring portion is provided with a presettingstate and an abutting state. In the presetting state, the anchoringportion is free from contact with the sealing portion. In the abuttingstate, the anchoring portion is in contact with the sealing portion. Theconnector is farther away from the sealing portion than the neckedopening portion along an axial direction of the anchoring portion in thepresetting state.

That is, when the sealing portion is moved toward the anchoring portion,the necked opening portion comes in contact with the bottom part of thesealing portion first, and meanwhile, the connector is still at adistance from the sealing portion, and this distance also allows afurther pulling to form the pre-tightening force.

In an embodiment, the connector is flush with the necked opening portionor farther away from the sealing portion than the necked opening portionalong the axial direction of the anchoring portion in the abuttingstate.

In an embodiment, the connector includes an outer ring and an inner ringnested within the outer ring. One of the first converging part and thesecond converging part extends through and is fixed in the inner ring,and the other one of the first converging part and the second convergingpart extends through and is fixed in a gap between the inner ring andthe outer ring.

In an embodiment, the connector includes an outer ring and an inner ringnested within the outer ring. One of the first converging part and thesecond converging part extends through and is fixed in a gap between theinner ring and the outer ring, and the other one of the first convergingpart and the second converging part penetrates through the inner ringand is provided with a retainer abutted against the connector. Theretainer is fixed to one end of the inner ring where the other one ofthe first converging part and the second converging part extends out.

In an embodiment, the connector includes a body having two passagesarranged side by side. The first converging part and the secondconverging part extend through the two passages respectively and areprovided with two retainers abutted against respective sides of thepassages where which the first converging part and the second convergingpart extend out correspondingly.

The connector and the retainer may be stainless steel, nickel titaniumalloy, or other metal material that meets biocompatibility requirements.

In an embodiment, the anchoring portion has an abutting portion thatabuts against the sealing portion. In a compressed state, the anchoringportion is in a cylindrical structure, and the abutting portion is on aninner wall of the cylindrical structure.

In an embodiment, the anchoring portion in a compressed state is in acylindrical structure, and an inner wall of the cylindrical structure ina released state abuts against the sealing portion.

When the left atrial appendage occluder is released, the anchoringportion bends outward, such that the abutting portion originally locatedon the inner wall of the cylindrical structure bends to be outside andfaces the sealing portion, and the abutting portion is further tightlyabutted against the sealing portion.

In the compressed state, if the abutting portion is on the outer wall ofthe cylindrical structure, the anchoring portion needs to bend in a morecomplicated manner, otherwise it is difficult for the anchoring portionto achieve a larger outer diameter to support and anchor at an innerwall of the left atrial appendage.

However, when the anchoring portion is to be bent in a complicatedmanner, the tendency of extending outward of an end terminal of theanchoring portion (i.e., a distal end of the anchoring portion in thecompressed state) can be changed, and the inner wall of the left atrialappendage can be prevented from being stabbed, thereby improving thesafety.

In an embodiment, the anchoring portion and the sealing portion aredirectly connected and abutted against each other in a using state.

In a normal using state, the anchoring portion may be in direct contactwith and abutted against the sealing portion. However, during using, theanchoring portion and the sealing portion are not always in the state ofdirectly contacting with and abutting against each other. Under theaction of a special anatomical structure or after being used for aperiod of time, the anchoring portion and the sealing portion may alsobe moved away from each other and even bring a gap created between theanchoring portion and the sealing portion.

In an embodiment, the sealing portion is a two-layer structure. Thetwo-layer structure includes a bottom layer facing the anchoring portionand a top layer facing away from the anchoring portion. The sealingportion is connected to the anchoring portion through the bottom layer.

Alternatively, a part of the anchoring portion extends through thesealing portion to connect with the top layer of the sealing portion. Inthe present disclosure, the anchoring portion is connected to the bottompart of the sealing portion, it is favorable for obtaining apre-deformation or a higher deformation efficiency of the sealingportion when the anchoring portion and the sealing portion are mutuallyabutted.

In an embodiment, one or more layers of flow blocking membrane areprovided inside the two-layer structure.

Since a sealing portion with a two-layer structure is more likely to beloose and elongated axially, the present disclosure is also preferablyapplicable to a sealing portion with a two-layer structure. Both asealing portion in a disc shape and in a column shape can be regarded asa two-layer structure with a flow blocking membrane provided inside.

In an embodiment, the sealing portion and the anchoring portion areformed individually and abut against each other during an assemblingprocess.

The sealing portion and the anchoring portion are formed separately andthermoformed individually and then are assembled together. Duringassembly, a pre-deformation effect can be obtained by causing thesealing portion and the anchoring portion abutted against each othertightly. If the sealing portion and the anchoring portion are formed inan integrated structure, an abutting effect can also be obtained.However, since the sealing portion and the anchoring portion are formedintegrally rather than assembled together, it is necessary to obtain theabutting effect after thermoforming, resulting in higher requirementsfor a thermoforming technic, and it is required that the sealing portionand the anchoring portion are separately thermoformed, therebyincreasing the processing difficulty.

In order to obtain a better effect of support and anchoring, theanchoring portions are deployed continuously circumferentially.

Although a mesh-like or a rod-like structure has some gaps along theaxial direction, it should be continuously extended in the axialdirection in terms of the overall structure and distribution, in orderto obtain a more uniform force distribution and stable support, and toavoid providing support merely by circumferentially local structure.

In an embodiment, a part of the anchoring portion abutted against thesealing portion is adjacent to an outer edge of the anchoring portion.

In an embodiment, a part of the sealing portion abutted against theanchoring portion is adjacent to an outer edge of the sealing portion.

The outer edges of the sealing portion and the anchoring portionabutting against each other facilitates an axial deformation or aradially convergence, and increasing deformation quantity under a sameforce.

In an embodiment, after thermoforming, the sealing portion and theanchoring portion are assembled together, and the sealing portion andthe anchoring portion are in a first state in an initial contact witheach other during assembly, and connection parts of the sealing portionand the anchoring portion are in a second state after axially moving apredetermined distance toward each other.

In the first state, the sealing portion and the anchoring portion havebeen and are just in contact with each other. Since both the sealingportion and the anchoring portion have been thermoformed, and when theyare further axially moved toward each other, one of them will deform andmaintain a stress caused by the deformation in the second state.

In an embodiment, the connection parts of the sealing portion and theanchoring portion are respectively disposed at middle parts of thesealing portion and the anchoring portion in a radial direction. In thefirst state, the sealing portion and the anchoring portion are incontact with each other at peripheral regions around the connectionparts respectively.

The pre-tightening force is also derived from the above-mentionedstress. If the thermoforming is performed after assembly rather thanbefore assembly, the stress will disappear during the thermoforming andthe pre-tightening force required cannot be created.

Therefore, it is noted that, in the second state, a relative positionalrelationship between the sealing portion and the anchoring portion isobtained after assembly, and the thermoforming is not performed afterthe second state.

Since the anchoring portion has greater stiffness, and generally, thestress is mainly generated from the deformation of the sealing portion.

In an embodiment, in the second state a part of the sealing portionconnected with the anchoring portion moved towards the anchoring portionwith respect to the first state.

In the second state, a distance in which the connection parts of thesealing portion and the anchoring portion axially move toward each otheraffects a magnitude of the stress, and therefore, it is necessary todefine and control the distance in an adaptive manner during assembly.

In an embodiment, the predetermined distance is defined according to oneof: an axial force of the connection parts between the sealing portionand the anchoring portion, a pressing force at contacting parts of thesealing portion and the anchoring portion, and a deformation of the partof the sealing portion connected with the anchoring portion.

In an embodiment, the deformation is an axial displacement of apredetermined part of the sealing portion, or an angle between thepredetermined part of the sealing portion and an axis of the sealingportion.

The predetermined part of the sealing portion is a part that is deformedfrom the first state to the second state. For ease of expression andmeasurement, a part with a larger deformation can be selected as thepredetermined part. For example, the predetermined part of the sealingportion is a part of the sealing portion in contact with the anchoringportion in the first state.

During assembly, the magnitude of the stress can be obtained bydetecting variations of the predetermined distance.

If it fails to provide such stress, even if there is a local contactbetween the sealing portion and the anchoring portion during assembly,when the left atrial appendage occluder is axially elongated as a wholeduring use (that is, the sealing portion and the anchoring portion areaway from each other), an inherent recovery force between the sealingportion and the anchoring portion is smaller, an overall axialelongation of the left atrial appendage occluder is counteracted merelyby the elasticity of the respective materials.

The left atrial appendage occluder according to the present disclosureis first thermoformed and then is assembled by retaining an axialstress, the overall axial elongation of the left atrial appendageoccluder in a subsequent use process can be better counteracted. Therecovery force is increased by superposing the pre-tightening force andresilient forces of the sealing portion and the anchoring portion,thereby ensuring the sealing effect for long-term use.

A method for manufacturing a left atrial appendage occluder is alsoprovided. The method is carried out as following. Thermoforming isperformed on a sealing portion and an anchoring portion. When assemblingthe sealing portion with the anchoring portion, the sealing portion andthe anchoring portion is moved toward each other to reach a first state,and in the first state the sealing portion and the anchoring portion arein initial contact with each other. The sealing portion and theanchoring portion is further moved axially toward each other apredetermined distance to reach a second state. And then, connectionparts of the sealing portion and the anchoring portion are fixedtogether, the connection parts are maintained in the second state tocomplete assembly.

Since the sealing portion and the anchoring portion have been in partialcontact with each other in the first state, and therefore, when the leftatrial appendage occluder is transformed into the second state from thefirst state, an axial distance between the overall sealing portion andthe anchoring portion is not changed, only a stress generated from localdeformations is changed.

A method for manufacturing a left atrial appendage occluder forimproving sealing effect is also provided. The method includesmanufacturing a sealing portion and an anchoring portion, and causingthe sealing portion to be tightly connected with and abutted against theanchoring portion.

The left atrial appendage occluder according to the present disclosureis delivered to the left atrial appendage of the heart by utilizing adelivery sheath in a percutaneous puncture mode, so as to block the leftatrial appendage and to avoiding a risk of a stroke in patients withatrial fibrillation due to thrombus formation in the left atrialappendage.

A tight connection between the sealing portion and the anchoring portionis realized by an improved connection manner according to the presentdisclosure, and a certain pre-tightening force is maintained to allowthe sealing portion to be tightly attached to the left atrial appendageto occlude an orifice of the left atrial appendage, thereby reducing theincidence of endoleaks and residual shunts.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view illustrating a left atrial appendage occluderaccording to a first embodiment;

FIG. 2 is a schematic view illustrating a sealing portion afterthermoforming according to the first embodiment;

FIG. 3 is a schematic view illustrating an anchoring portion afterthermoforming according to the first embodiment;

FIG. 4A is a schematic view illustrating a process of connecting theanchoring portion and the sealing portion (only the anchoring portion isillustrated) according to the first embodiment;

FIG. 4B is an enlarged view illustrating a part indicated by circle A inFIG. 4A;

FIG. 5 is a schematic view illustrating the process of connecting theanchoring portion and the sealing portion (only the sealing portion isillustrated) according to the first embodiment;

FIG. 6 is a schematic view illustrating that the anchoring portion andthe sealing portion start to connect according to the first embodiment;

FIG. 7A is a schematic view illustrating that a connection between theanchoring portion and the sealing portion is completed according to thefirst embodiment;

FIG. 7B is a schematic view illustrating a connection between a sealingportion and an anchoring portion in the related art;

FIG. 7C is a schematic view illustrating the anchoring portion and thesealing portion illustrated in FIG. 7A with a part omitted;

FIG. 8 is a schematic view illustrating a left atrial appendage occluderreleased in a left atrial appendage according to the first embodiment;

FIG. 9A is a schematic view illustrating a left atrial appendageoccluder according to a second embodiment;

FIG. 9B is an enlarged view illustrating a part indicated by circle A inFIG. 9A;

FIG. 10 is a schematic view illustrating a process of connecting ananchoring portion and a sealing portion according to the secondembodiment;

FIG. 11A is a schematic view illustrating a left atrial appendageoccluder according to a third embodiment;

FIG. 11B is an enlarged view illustrating a part indicated by circle Ain FIG. 11A;

FIG. 12A is a schematic view illustrating a process of connecting theanchoring portion and the sealing portion according to a thirdembodiment;

FIG. is an enlarged view illustrating a part indicated by circle A inFIG. 12A;

FIG. 13 is a schematic view illustrating a process of connecting ananchoring portion and a sealing portion according to the thirdembodiment;

FIG. 14 is a schematic view illustrating a left atrial appendageoccluder according to a fourth embodiment;

FIGS. 15-17 are schematic views illustrating a process of releasing ananchoring portion according to a fifth embodiment, and the sealingportion is in a released state;

FIGS. 18-20 are schematic views illustrating sealing portions with discbottoms in various shapes according to the fifth embodiment;

FIGS. 21-25 are schematic views comparing the disc bottom before andafter deformation according to the fifth embodiment;

FIGS. 26-28 are schematic views comparing the disc bottom in anothershape before and after deformation according to the fifth embodiment;

FIGS. 29-30 are schematic views comparing a disc bottom before and afterdeformation according to a sixth embodiment;

FIGS. 31-40 are schematic views illustrating a left atrial appendageoccluder before and after assembly in various connection mannersaccording to a seventh embodiment.

DETAILED DESCRIPTION OF ILLUSTRATED EMBODIMENTS First Embodiment

As illustrated in FIG. 1 , the left atrial appendage occluder 1000 inthe first embodiment of the present disclosure includes a sealingportion 1100 and an anchoring portion 1200 coupled to the sealingportion 1100. The sealing portion 1100 and the anchoring portion 1200each are formed by weaving nickel-titanium wires.

The sealing portion 1100 includes a disc surface 1110, an intermediatepart 1120, and a disc bottom 1170. An end of the disc surface 1110 isprovided with a holding head 1130. One layer of PET flow blockingmembrane 1140 is sutured inside the disc surface, one layer of flowblocking membrane 1150 is sutured inside a middle part of theintermediate part 1120, and one layer of flow blocking membrane 1160 issutured inside the disc bottom 1170.

The anchoring portion 1200 includes an inner mesh-shaped cone 1210, anouter mesh-shaped cylinder 1220, an outer end bent portion 1230, an arctransition portion 1240 connected between the inner mesh-shaped cone1210 and the outer mesh-shaped cylinder 1220, and an arc transitionportion 1250 connected between the outer mesh-shaped cylinder 1220 andthe outer end bent portion 1230. Multiple barbs 1270 are arrangeduniformly circumferentially an outer surface of the outer mesh-shapedcylinder 1220.

The inner mesh-shaped cone 1210 forms an extending portion, the outermesh-shaped cylinder 1220 forms a turning-back portion, and the outerend bent portion 1230 forms a necked opening portion.

A distal end of the disc bottom 1170 of the sealing portion 1100 (thatis, an end of the disc bottom 1170 closer to the anchoring portion 1200)is connected with a proximal end of the inner mesh-shaped cone 1210 ofthe anchoring portion 1200 (that is, an end of the inner mesh-shapedcone 1210 closer to the sealing portion 1100) in a rigid-sleevefastening manner or a laser welding manner.

Before being connected with each other, the sealing portion 1100 and theanchoring portion 1200 are individually shaped by a cylindrical wovennickel-titanium mesh through high-temperature heat treatment within amold. FIG. 2 illustrates the sealing portion 1100 of the left atrialappendage occluder 1000 shaped through thermoforming according to thefirst embodiment of the present disclosure. FIG. 3 illustrates theanchoring portion 1200 of the left atrial appendage occluder 1000 shapedthrough thermoforming according to the first embodiment of the presentdisclosure. The sealing portion 1100 is provided with a distalnickel-titanium wire which is constricted and converged, and theanchoring portion 1200 is provided with a proximal nickel-titanium wirewhich is constricted and converged.

FIGS. 4A-7 illustrate a connection manner of the sealing portion 1100and the anchoring portion 1200 of the left atrial appendage occluder1000 according to the first embodiment of the present disclosure.

The proximal nickel-titanium wire 1261 of the anchoring portion 1200 isconverged and fixed between an outer steel sleeve 1262 (equivalent to anouter ring) and an inner steel sleeve 1263 (equivalent to an innerring). It can be seen that the nickel-titanium wire used for weaving theanchoring portion 1200 is constricted and converged at a proximal end ofthe extending portion and is connected between the inner steel sleeve1263 and the outer steel sleeve 1262 serving as a connector. As can beseen in FIG. 4A, the inner steel sleeve 1263 and the outer steel sleeve1262 serving as the connector are disposed farther away from the sealingportion 1100 than the necked opening portion. The anchoring portion 1200in a turning-up structure is substantially in a shape of a bowl (ornest), and the connector is disposed within the bowl and below anopening of the bowl.

The inner steel sleeve 1263, the outer steel sleeve 1262, and theproximal nickel-titanium wire 1261 extending between the inner steelsleeve 1263 and the outer steel sleeve 1262 are fixed together bywelding or in a pressing manner. The inner steel sleeve 1263 is in ahollow structure, and an excess portion of the proximal nickel-titaniumwire 1261 extending beyond a proximal end of the outer steel sleeve 1262is removed by shearing or laser processing.

As illustrated in FIG. 5 and FIG. 6 , the distal nickel-titanium wire1171 of the sealing portion 1100 is converged at a middle part of thedisc bottom 1170 and extends through the inner steel sleeve 1263. Acertain pulling force can be applied to tightly connect the sealingportion 1100 and the anchoring portion 1200 to generate a certainpre-tightening force. The pre-tightening force enables the intermediatepart 1120 of the sealing portion 1100 to form a tapered structure, andmeanwhile an overall height of the left atrial appendage occluder 1000can be reduced.

FIGS. 7A-7C illustrate a structure of the sealing portion 1100. Thedistal nickel-titanium wire 1171 of the sealing portion 1100 is fixedwith a steel sleeve 1172 (equivalent to a retainer). The steel sleeve1172 can be slidably moved along the distal nickel-titanium wire 1171 toabut against a distal end of the inner steel sleeve 1263 and be furtherfixed to the distal nickel-titanium wire 1171. An outer diameter of thesteel sleeve 1172 is larger than an inner diameter of the inner steelsleeve 1263 to prevent the distal nickel-titanium wire 1171 fromdisengaging off from the inner steel sleeve 1263.

An excess portion of the distal nickel-titanium wire 1171 extendingbeyond a distal end of the sealing portion 1100 is removed by shearingor laser processing. A material of the steel sleeve according to thepresent disclosure may be stainless steel, nickel-titanium alloy, orother metal material that meets biocompatibility requirements. In thisembodiment, the material of the steel sleeve is stainless steel.

During assembling, the sealing portion 1100 and the anchoring portion1200 are moved toward each other. When the sealing portion 1100 and theanchoring portion 1200 are just in contact with each other, the sealingportion 1100 and the anchoring portion 1200 is in a first state. As thedistal nickel-titanium wire 1171 is further pulled axially, a side ofthe sealing portion 1100 facing the anchoring portion 1200 increasinglytightly abuts against the anchoring portion 1200 to generate a stress(i.e., the pre-tightening force). When the distal nickel-titanium wire1171 is pulled axially a predetermined distance, the sealing portion1100 and the anchoring portion 1200 is in a second state, and at thistime, the sealing portion 1100 and the anchoring portion 1200 arefurther kept in the second state via the steel sleeve 1172, such thatthe stress is maintained.

The predetermined distance that the distal nickel-titanium wire 1171 ispulled axially may be directly obtained by measurements, or may beobtained according to changes in a shape of the side of the sealingportion 1100 facing the anchoring portion 1200 (i.e., the disc bottom1170), or may be obtained by directly measuring a tensile force of thedistal nickel-titanium wire 1171 or a stress between the sealing portion1100 and the anchoring portion 1200.

The changes in the shape of the disc bottom 1170 can be determined bycomparing with the shape of the disc bottom 1170 itself in the firststate, and can also be determined by comparing with an angle between thedisc bottom 1170 and the intermediate part 1120 or an angle between thedisc bottom 1170 and an axial of the sealing portion 1100.

Compared with the sealing portion 1100 and the anchoring portion 1200illustrated in FIG. 6 , the sealing portion 1100 and the anchoringportion 1200 in the first state are further brought into just contactwith each other. Since the shape of the sealing portion 1100 areunchanged, the shape of the sealing portion 1100 in the first state canrefer to that illustrated in FIG. 6 . As illustrated in FIG. 6 and FIG.7A, it can be clearly seen that in the first state, the disc bottom 1170is substantially perpendicular to the intermediate part 1120, and in thesecond state as illustrated in FIG. 7A, the angle between the discbottom 1170 and the intermediate part 1120 is increased, and the middlepart of the disc bottom 1170 in a radial direction further protrudestoward the anchoring portion 1200. Therefore, the predetermined distancethat the distal nickel-titanium wire 1171 is pulled axially can beindicated and controlled with respect to changes in the angle.

After the sealing portion 1100 is connected to the anchoring portion1200, one layer of PET flow blocking membrane 1140 is sutured inside thedisc surface of the sealing portion 1100 of the left atrial appendageoccluder 1000, one layer of flow blocking membrane 1150 is suturedinside the middle part of the intermediate part 1120 of the sealingportion 1100, and one layer of flow blocking membrane 1160 is suturedinside the disc bottom 1170 of the sealing portion 1100, as illustratedin FIG. 1 .

The sealing portion 1100 is a cage-shaped structure having a certaininternal space as a whole, and in a presetting state, the intermediatepart is in a substantially cylindrical shape. It can be seen bycomparing FIG. 2 with FIG. 7A, after assembly, the disc bottom 1170 andthe necked opening portion are tightly abutted against each other, and adistal end of the intermediate part is radially constricted to have acertain taper and forms a substantially inverted-cone-shaped structure.Moreover, the middle part of the disc bottom 1170 protrudes toward theanchoring portion 1200 under the action of the pre-tightening force.

Referring to FIG. 7B, in the related art, the sealing portion 1100 isprovided with a connection part 1180, and the anchoring portion 1200 isprovided with a connection part 1280. The connection part 1180 of thesealing portion 1100 and the connection part 1280 of the anchoringportion 1200 are arranged in align with and extend toward each other.When the connection part 1180 and the connection part 1280 come incontact with each other, the connection part 1180 and the connectionpart 1280 are fixedly connected together by welding or via an annularhoop.

It can be seen that, since a larger gap exists between the sealingportion 1100 and the anchoring portion 1200, the sealing effect needs tobe improved.

In this embodiment, the sealing portion 1100 and the anchoring portion1200 have respective converging parts operating as the connection parts.As illustrated in FIG. 5 , the connection part of the sealing portion1100 (i.e., the converged distal nickel-titanium wire 1171) is formed byconverging the disc bottom 1170, that is, the disc bottom 1170 with alarger cross-section area converges abruptly to form one wire strandwith a smaller cross-section area.

Combining with the FIG. 4A, it can be seen that, the connection part1280 of the anchoring portion 1200, namely, the proximal nickel-titaniumwire 1261 which has been converged, gradually transforms into a strandwith a smaller cross-section area from the inner mesh-shaped cone 1210.

Referring to FIG. 7C, after assembly, the connection part of theanchoring portion 1200 is fixed between the outer steel sleeve 1262 andthe inner steel sleeve 1263, and the connection part of the sealingportion 1100 extends through the inner steel sleeve 1263 and is fixedwith the steel sleeve 1172 abutted against the distal end of the innersteel sleeve 1263. In this connection manner, the connection part of thesealing portion 1100 extends through a center void space inside theconnection part of the anchoring portion 1200, and the connection partof the anchoring portion 1200 is disposed around the connection part ofthe sealing portion 1100, such that two connection parts are arrangedwith one connection part nested within the other connection part, andeach of two connection parts extends beyond a terminal end of the otherconnection part.

As seen from a direction of an axial of the left atrial appendageoccluder (i.e., direction A illustrated in FIG. 7C), the connection partof the sealing portion 1100 is nested within the connection part of theanchoring portion 1200. The connection part of the sealing portion 1100and the connection part of the anchoring portion 1200 individuallyextend along a straight line (that is, extend along the direction of theaxial of the left atrial appendage occlude). Due to the staggeredarrangement, the connection part of the anchoring portion 1200 and theconnection part of the sealing portion 1100 extend without spatiallyinterference with each other, such that an axial distance between thesealing portion 1100 and the anchoring portion 1200 can be decreased asmuch as possible until peripheral regions each around the connectionparts of the anchoring portion 1200 and the sealing portion 1100,respectively, are tightly abutted against one another.

As seen from a direction perpendicular to the axial of the left atrialappendage occluder (i.e., direction B illustrated in FIG. 7C), theconnection part of the anchoring portion 1200 and the connection part ofthe sealing portion 1100 overlap each other, and a projection of theconnection part of the sealing portion 1100 in direction B falls withinthe connection part of the anchoring portion 1200.

In this embodiment, the sealing portion 1100 is integrated with theconnection part of the sealing portion 1100, and the anchoring portion1200 is integrated with the connection part of the anchoring portion1200. Alternatively, it is also possible that the sealing portion 1100and the anchoring portion 1200 are formed without wire strands extendingtoward each other and provided with their respective connection rodsinstead. That is, the sealing portion 1100 and the anchoring portion1200 are provided individually with their respective connection rods.The connection rods each are disposed at middle parts of opposite sidesof the sealing portion 1100 and the anchoring portion 1200 respectively,and one of the connection rods is in a shape of a hollow structure, andthe other connection rod extends through the one connection rod, suchthat a connection between the sealing portion 1100 and the anchoringportion 1200 in the staggered manner can also be realized.

As illustrated in FIG. 8 , when the left atrial appendage occluder 1000in this embodiment is delivered into the left atrial appendage via apercutaneous catheter delivery system, the left atrial appendageoccluder 1000 is anchored in the left atrial appendage. The anchoringportion 1200 is connected to the sealing portion 1100 such that thepre-tightening force is formed between the sealing portion 1100 and theanchoring portion 1200, and the intermediate part 1120 in a taperedshape of the left atrial appendage occluder 1000 can be more closelyattached to an orifice of the left atrial appendage. The pre-tighteningforce allows the disc surface 1110 of the sealing portion 1100 to beattached to the left atrial appendage more closely, such that thethree-layered membrane effectively blocks blood from flowing into theleft atrial appendage to reduce the incidence of endoleaks.

Second Embodiment

In the second embodiment according to the present disclosure, the leftatrial appendage occluder 2000 includes a sealing portion 2100 and ananchoring portion 2200. After thermoforming, a shape of the sealingportion 2100 and a shape of the anchoring portion 2200 are the same asthat in the first embodiment respectively. Compared with the firstembodiment, a connection manner between the sealing portion 2100 and theanchoring portion 2200 is different, as illustrated in FIG. 9A and FIG.9B.

In the second embodiment of the present disclosure, the left atrialappendage occluder 2000 includes the sealing portion 2100 and theanchoring portion 2200 after thermoforming. The sealing portion 2100 isprovided with a distal nickel-titanium wire which is constricted andconverged, and the anchoring portion 2200 is provided with a proximalnickel-titanium wire which is constricted and converged.

As illustrated in FIG. 10 , a distal nickel-titanium wire 2171 of thesealing portion 2100 and a proximal nickel-titanium wire 2261 of theanchoring portion 2200 in this embodiment are individually processed tobe constricted and converged, and then extend through a steel sleeve2272 (equivalent to a body of a connector) from opposite directionsrespectively.

Two pulling forces are applied to the distal nickel-titanium wire 2171and the proximal nickel-titanium wire 2261 along directions indicated byarrows illustrated in FIG. 10 correspondingly, such that the sealingportion 2100 and the anchoring portion 2200 are tightly connected witheach other to generate a certain pre-tightening force between thesealing portion 2100 and the anchoring portion 2200, and thepre-tightening force allows the intermediate part 2120 of the sealingportion 2100 to be stretched into a shape of a tapered structure.Furthermore, as illustrated in FIG. 9B, the proximal nickel-titaniumwire 2261 of the anchoring portion 2200 extends through a steel sleeve2172 and is fixed with the steel sleeve 2172 by welding or in a pressingmanner, and the distal nickel-titanium wire 2171 of the sealing portion2100 extends through a steel sleeve 2263 and is fixed with the steelsleeve 2263 by welding or in a pressing manner. The steel sleeve 2172and the steel sleeve 2263 are engaged on either sides of a steel sleeve2272, and an excess portion of the proximal nickel-titanium wire 2261extending beyond an distal end of the steel sleeve 2172 and an excessportion of the distal nickel-titanium wire 2171 extending beyond anproximal end of the steel sleeve 2263 are removed by shearing or laserprocessing.

As illustrated in FIG. 9B, the sealing portion 2100 and the anchoringportion 2200 in this embodiment are also provided in a similar manner tothe first embodiment, and each have and are integrated with theirconnection parts extending toward each other, respectively. Comparedwith the sealing portion 1100 and the anchoring portion 1200 in thefirst embodiment, the two connection parts of the sealing portion 2100and the anchoring portion 2200 are staggered from each other in amutually offset manner. According to the orientations illustrated inFIG. 9B, one of the two connection parts is to the left and the other isto the right.

In this way, it is also possible to avoid spatial interference betweenthe two connection parts when extending toward each other, such that thesealing portion 2100 and the anchoring portion 2200 can be brought toeach other as close as possible.

Third Embodiment

In the third embodiment according to the present disclosure, the leftatrial appendage occluder 3000 includes a sealing portion 3100 and ananchoring portion 3200. After thermoforming, a shape of the sealingportion 3100 and a shape of the anchoring portion 3200 are the same asthat in the first embodiment, as well as the second embodiment,respectively. Compared with the first embodiment as well as the secondembodiment, a connection manner between the sealing portion 3100 and theanchoring portion 3200 is different, as illustrated in FIG. 11A and FIG.11B.

In the third embodiment of the present disclosure, the left atrialappendage occluder 3000 includes the sealing portion 3100 and theanchoring portion 3200 after thermoforming. The sealing portion 3100 isprovided with a distal nickel-titanium wire which is constricted andconverged, and the anchoring portion 3200 is provided with a proximalnickel-titanium wire which is constricted and converged. FIGS. 12A-13illustrate another connection manner between the sealing portion 3100and the anchoring portion 3200 of the left atrial appendage occluder3000 according to the third embodiment of the present disclosure.

In the left atrial appendage occluder 3000 of this embodiment, a distalnickel-titanium wire 3171 of the anchoring portion 3100 is converged andextends between an outer steel sleeve 3172 and an inner steel sleeve3173, and the outer steel sleeve 3172 and the inner steel sleeve 3173,and the distal nickel-titanium wire 3171 extending between the outersteel sleeve 3172 and the inner steel sleeve 3173 are fixed together bywelding or in a pressing manner. The inner steel sleeve 3173 is in ashape of a hollow structure, and an excess portion of the distalnickel-titanium wire 3171 extending beyond distal ends of the outersteel sleeve 3172 and the inner steel sleeve 3173 is removed by shearingor laser processing.

The proximal nickel-titanium wire 3261 of the anchoring portion 3200 isconverged and extends through the inner steel sleeve 3173 disposed at adistal end of the sealing portion 3200 to extend into a middle part ofthe sealing portion 3100. A certain pulling force can be applied totightly connect the sealing portion 3100 with the anchoring portion 3200to generate a certain pre-tightening force, and the pre-tightening forceenables an intermediate part of the sealing portion 3100 to be reshapedin a tapered structure. Further, the proximal nickel-titanium wire 3261of the anchoring portion 3200 is fixed together with a steel sleeve3162. An outer diameter of the steel sleeve 3162 is larger than an innerdiameter of the inner steel sleeve 3173, and an excess portion of theproximal nickel-titanium wire 3261 extending beyond a proximal end ofthe anchoring portion 3200 is removed by shearing or laser processing.

Fourth Embodiment

Compared with the first embodiment, the shape of a sealing portion 4100in the fourth embodiment is different, as illustrated in FIG. 14 .

In this embodiment, the sealing portion 4100 is in a substantially flatdisk shape, that is, the sealing portion 4100 is a sealing disk. Underthe action of a pre-tightening force, a middle part of the sealing diskprotrudes toward the anchoring portion.

Fifth Embodiment

This embodiment mainly illustrates a release of an anchoring portion5200 and changes in the shape of a sealing portion 5100 during assembly.Specific structures of the anchoring portion 5200 and the sealingportion 5100 can refer to at least one of the first embodiment, thesecond embodiment, and the third embodiment.

As illustrated in FIGS. 15-17 , the left atrial appendage occluder inthis embodiment includes the sealing portion 5100 and the anchoringportion 5200 coupled to the sealing portion 5100. The anchoring portion5200 is compressed and received within a sheath tube before beingreleased, thereby facilitating the left atrial appendage occluder to bedelivered to a lesion in a body. In a compressed state, the anchoringportion 5200 is in a cylindrical structure, and portion A is positionedon an inner wall of the cylindrical structure. When the anchoringportion 5200 is released in a turning-up manner (a direction ofturning-up can refer to a direction indicated by an arrow illustrated inFIG. 16 ), portion A on the inner wall of the cylindrical structure isgradually bent outward, and finally abuts against a disc bottom of thesealing portion 5100.

As illustrated in FIGS. 18-20 , the sealing portion 5100 includes a discsurface, an intermediate part, and a disc bottom 5110. A central part ofthe disc bottom 5110 (that is, a part of the disc bottom 5110 disposedin a center of the disc bottom 5110) is constricted and converged toform a distal nickel-titanium wire 5120, and the distal nickel-titaniumwire 5120 extends through a connector 5210 of the anchoring portion 5200(such as, a steel sleeve, or the like).

The shape of a middle part of the disc bottom 5110 (that is, a part ofthe disc bottom 5110 disposed in a middle of the disc bottom 5110)varies in various examples. As illustrated in FIG. 18 , the middle partof the disc bottom 5110 may be recessed away from the anchoring portion5200. As illustrated in FIG. 19 , the middle part of the disc bottom5110 may be in a substantially flat shape. As illustrated in FIG. 20 ,the middle part of the disc bottom 5110 may be protruded toward theanchoring portion 5200.

The above examples illustrate characteristics of the shape of the discbottom 5110 before completing the assembly of the left atrial appendageoccluder (i.e., a pre-tightening force is not applied). When thepre-tightening force is applied, the middle part of the disc bottom 5110has different degrees of deformation and is generally further movedtoward the anchoring portion 5200.

Referring to FIGS. 21-25 , taking the disc bottom 5110 in one shape asan example, the sealing portion 5100 and the anchoring portion 5200 areassembled together after being individually processed and thermoformed.The distal nickel-titanium wire 5120 first extends through the connector5210 of the anchoring portion 5200 to enable the sealing portion 5100and the anchoring portion 5200 to move axially toward each other.

As illustrated in FIG. 22 , the sealing portion 5100 and the anchoringportion 5200 are in a first state. In the first state, the sealingportion 5100 and the anchoring portion 5200 are just in contact witheach other and the pre-tightening force is not applied, and middleregion C of the disc bottom 5110 has a tendency to recess away from theanchoring portion 5200. The distal nickel-titanium wire 5120 is thenpulled downward in a direction of a downward-arrow illustrated in FIG.23 , and the connector 5210 of the anchoring portion 5200 moves upwardin a direction of an upward-arrow, such that middle region C is deformedto generate a predetermined deformation or to meet requirements of apre-tightening force. Furthermore, the distal nickel-titanium wire 5120is fixed with a retainer 5130, at this time, the sealing portion 5100and the anchoring portion 5200 are in a second state. As illustrated inFIG. 24 , the middle region C is deformed into a substantially flatshape.

A change of angle B or an axial deformation H of middle region C can beacquired when the pre-tightening force is applied, so as to control anassembling process. A deformation of middle region C is more clearlyillustrated by a comparison indicated in FIG. 25 , and a dotted lineindicates a position of middle region C in the first state.

Referring to FIGS. 26-28 , in another implementation, the sealingportion 5100 and the anchoring portion 5200 are in the first state. Inthe first state, the sealing portion 5100 and the anchoring portion 5200are just in contact with each other and the pre-tightening force is notapplied, and middle region C of the disc bottom 5110 has a tendency torecess away from the anchoring portion 5200. During assembling, thedistal nickel-titanium wire 5120 is pulled downward and the connector5210 of the anchoring portion 5200 moves upward until middle region C isdeformed to generate a predetermined deformation or to meet requirementsof a pre-tightening force. Furthermore, the distal nickel-titanium wire5120 is fixed with a retainer 5130, and at this time, the sealingportion 5100 and the anchoring portion 5200 are in the second state.When middle region C is forced to deform, the intermediate part of thesealing portion 5100 is converged radially along a direction of an arrowillustrated in FIG. 27 . In the second state, as more clearlyillustrated by a comparison indicated in FIG. 28 , the intermediate parttogether with the disc bottom 5110 are in an inverted-cone-shape as awhole, and a dotted line in FIG. 28 indicates a position of theintermediate part and middle region C in the first state.

Sixth Embodiment

Referring to FIG. 29 and FIG. 30 , the left atrial appendage occluder inthis embodiment includes a sealing portion 6100 and an anchoring portion6200. In the first state, a side of the sealing portion 6100 facing theanchoring portion 6200 is provided with a disc bottom 6110 in aninverted-cone-shaped. A central part of the disc bottom 6110 (that is, apart of the disc bottom 6110 disposed in a center of the disc bottom6110) is constricted and converged to form a distal nickel-titanium wire6120, and the distal nickel-titanium wire 6120 extends through aconnector 6210 of the anchoring portion 6200 (such as, a steel sleeve,or the like).

In the second state after assembly, a middle part of the disc bottom6110 (that is, a part of the disc bottom 6110 disposed in a middle ofthe disc bottom 6110) is further brought closer to the connector 6210, ataper of the middle part of the disc bottom 6110 is increased, and thedistal nickel-titanium wire 6120 is locked in an axial position via aretainer 6130.

Seventh Embodiment

This embodiment mainly illustrates a different connection manner betweenan anchoring portion 7200 and a sealing portion 7100. Specificstructures of the anchoring portion 7200 and the sealing portion 7100can refer to at least one of the other embodiments.

Referring to figures provided in this embodiment, the left atrialappendage occluder includes a sealing portion 7100 and an anchoringportion 7200 coupled with the sealing portion 7100. The sealing portion7100 includes a disc surface, an intermediate part, and a disc bottom7110.

As illustrated in FIG. 31 and FIG. 32 , a central part of a disc bottom7110 is constricted and converged to form a connection part, that is,the central part of the disc bottom 7110 is converged to form a distalnickel-titanium wire 7120. A middle part of the anchoring portion 7200is wholly converged to form a connection part, and an end of theconnection part of the anchoring portion 7200 is fixed with a connector7210 (for example, a steel sleeve). When assembling, the distalnickel-titanium wire 7120 extends through a hollow portion of theconnector 7210 of the anchoring portion 7200 and is tensioned againstthe anchoring portion 7200 to generate a pre-tightening force. When theanchoring portion 7200 and the sealing portion 7100 abut tightly againsteach other, and a middle part of the disc bottom 7110 is deformed tofurther protrude toward the anchoring portion 7200. Finally, the distalnickel-titanium wire 7120 is fixed with the retainer 7130 (for example,a steel hoop), and an excess portion of the distal nickel-titanium wire7120 beyond a distal end of the retainer 7130 is cut off to completeassembly.

In another implementation, as illustrated in FIG. 33 and FIG. 34 , thecentral part of the disc bottom 7110 is constricted and converged toform the connection part, that is, the central part of the disc bottom7110 is converged to form the distal nickel-titanium wire 7120.

The middle part of the anchoring portion 7200 is wholly converged toform a proximal nickel-titanium wire 7220. A connector 7210 with twopassages arranged side by side is provided, and the distalnickel-titanium wire 7120 and the proximal nickel-titanium wire 7220extend through the two passages correspondingly in opposite directionsand are oppositely tensioned to generate a pre-tightening force. Whenthe anchoring portion 7200 and the sealing portion 7100 abut tightlyagainst each other, and the middle part of the disc bottom 7110 isdeformed to further protrude toward the anchoring portion 7200. Finally,the distal nickel-titanium wire 7120 is fixed with the retainer 7130(for example, a steel hoop), and an excess portion of the distalnickel-titanium wire 7120 beyond a distal end of the retainer 7130 iscut off. Further, the proximal nickel-titanium wire 7220 is fixed with aretainer 7230 (for example, a steel hoop), and an excess portion of theproximal nickel-titanium wire 7220 beyond a proximal end of the retainer7230 is cut off to complete assembly.

In another implementation, as illustrated in FIG. 35 and FIG. 36 , thecentral part of the disc bottom 7110 is constricted and converged toform the connection part, and an end of the connection part of theanchoring portion 7200 is fixed with a connector 7140 (for example, asteel sleeve). The central part of the anchoring portion 7200 is whollyconverged to form the proximal nickel-titanium wire 7220. The proximalnickel-titanium wire 7220 extends through a hollow portion of theconnector 7140 and is tensioned against the anchoring portion 7200 togenerate the pre-tightening force. When the anchoring portion 7200 andthe sealing portion 7100 abut tightly against each other, and the middlepart of the disc bottom 7110 is deformed to further protrude toward theanchoring portion 7200. The proximal nickel-titanium wire 7220 is fixedwith a retainer 7230 (for example, a steel hoop), and an excess portionof the proximal nickel-titanium wire 7220 beyond a proximal end of theretainer 7230 is cut off to complete assembly.

In another implementation, as illustrated in FIG. 37 and FIG. 38 , thecentral part of the disc bottom 7110 is constricted and converged toform the connection part, that is, the central part of the disc bottom7110 is converged to form the distal nickel-titanium wire 7120. Themiddle part of the anchoring portion 7200 is wholly converged to form aproximal nickel-titanium wire 7220.

The distal nickel-titanium wire 7120 and the proximal nickel-titaniumwire 7220 are directly connected with each other, that is, a connectoris omitted. As illustrated in FIG. 38 , the proximal nickel-titaniumwire 7220 is wound around an outer periphery of the distalnickel-titanium wire 7120. An end of the distal nickel-titanium wire7120 may be provided with a retainer 7130 (for example, a steel hoop),and an end of the proximal nickel-titanium wire 7220 may be fixed at adisc bottom of the sealing portion 7100 by welding. In addition, theproximal nickel-titanium wire 7220 may be in a spiral shape andthermoformed in advance, and can be rewound around the outer peripheryof the distal nickel-titanium wire 7120 after overcoming an elasticforce to uncoil the proximal nickel-titanium wire 7220. Moreover, thedistal nickel-titanium wire 7120 can also be interwound with theproximal nickel-titanium wire 7220 in a spiral manner.

In another implementation, as illustrated in FIG. 39 and FIG. 40 , thedisc bottom 7110 is wholly converged to form a connection part, that is,the disc bottom 7110 is wholly converged to form the distalnickel-titanium wire 7120. The middle part of the anchoring portion 7200is wholly converged to form a connection part, and an end of theconnection part of the anchoring portion 7200 is fixed with a connector7210 (for example, a steel sleeve). During assembling, the distalnickel-titanium wire 7120 extends through a hollow portion of theconnector 7210 of the anchoring portion 7200 and is tensioned againstthe anchoring portion 7200 to generate the pre-tightening force.Finally, the distal nickel-titanium wire 7120 is fixed with the retainer7130 (for example, a steel hoop), and an excess portion of the distalnickel-titanium wire 7120 beyond a distal end of the retainer 7130 iscut off to complete assembly.

The above embodiments are only specific embodiments of the presentdisclosure, but the present disclosure is not limited thereto. As willoccur to those skilled in the art, the present disclosure is susceptibleto various modifications and variations without departing from thespirit and principle of the present disclosure. It is obvious that thesemodifications and variations are within the scope of the presentdisclosure. In addition, although specific terms are adopted in thespecification, these terms are merely for convenience of description anddo not impose any particular limitation on the present disclosure.

What is claimed is:
 1. A left atrial appendage occluder for improvingsealing effect, comprising: a sealing portion; and an anchoring portioncoupled to the sealing portion; wherein the sealing portion and theanchoring portion are abutted against each other, wherein peripheralregions of the anchoring portion and the sealing portion are abuttedagainst each other, the peripheral regions of the anchoring portion andthe sealing portion are regions around connection parts of the anchoringportion and the sealing portion.
 2. The left atrial appendage occluderfor improving sealing effect of claim 1, wherein the sealing portioncomprises a disc surface facing away from the anchoring portion, a discbottom facing the anchoring portion, and an intermediate part connectingthe disc surface and the disc bottom, and wherein the disc bottom isplanar, or a middle part of the disc bottom protrudes toward theanchoring portion, or the middle part of the disc bottom protrudes awayfrom the anchoring portion.
 3. The left atrial appendage occluder forimproving sealing effect of claim 2, wherein the sealing portion isprovided with a presetting state and an abutting state, and wherein inthe presetting state the sealing portion is free from contact with theanchoring portion, and in the abutting state the sealing portion is incontact with the anchoring portion, and wherein a diameter of the discbottom in the presetting state is larger than a diameter of the discbottom in the abutting state.
 4. The left atrial appendage occluder forimproving sealing effect of claim 2, wherein the sealing portion isprovided with a presetting state and an abutting state, and wherein inthe presetting state the sealing portion is free from contact with theanchoring portion, and in the abutting state the sealing portion is incontact with the anchoring portion, and wherein at least one of theintermediate part and the disc bottom of the sealing portion in theabutting state has a deformation with respect to the presetting state.5. The left atrial appendage occluder for improving sealing effect ofclaim 4, wherein the intermediate part of the sealing portion in theabutting state has a radially contracted deformation with respect to thepresetting state, and the disc bottom of the sealing portion in theabutting state has a deformation protruding toward the anchoring portionaxially with respect to the presetting state.
 6. The left atrialappendage occluder for improving sealing effect of claim 1, whereinconnection parts of the sealing portion and the anchoring portion areconnected in a staggered manner.
 7. The left atrial appendage occluderfor improving sealing effect of claim 1, wherein: the sealing portionand the anchoring portion are constricted and converged respectively,and the sealing portion and the anchoring portion are connected togethervia a connector; the sealing portion comprises a bottom part facing theanchoring portion, and the bottom part of the sealing portion comprisesa first converging part; a middle part of the anchoring portion in aradial direction comprises a second converging part; and the firstconverging part and the second converging part extend toward each otherand are fixed together in a staggered manner.
 8. The left atrialappendage occluder for improving sealing effect of claim 7, wherein thefirst converging part and the second converging part are arrangedside-by-side in the staggered manner or are arranged in a nesting insideand outside in the staggered manner.
 9. The left atrial appendageoccluder for improving sealing effect of claim 7, wherein: the anchoringportion extends from the connector away from the sealing portion to forman extending portion; one side of the extending portion facing away fromthe connector is bent outward and turns back to the bottom part of thesealing portion to form a turning-back portion; the turning-back portionbends inward and is constricted at the bottom part of the sealingportion to form a necked opening portion; and the necked opening portionabuts against the bottom part of the sealing portion.
 10. The leftatrial appendage occluder for improving sealing effect of claim 9,wherein the necked opening portion is suspended above a periphery of theextending portion or connected to the extending portion, the extendingportion is in a tapered shape, and an end of the extending portionhaving a larger diameter is disposed away from the connector and isprovided with an opening.
 11. The left atrial appendage occluder forimproving sealing effect of claim 9, wherein the anchoring portion isprovided with a presetting state and an abutting state, and wherein inthe presetting state the anchoring portion is free from contact with thesealing portion, and wherein in the abutting state the anchoring portionis in contact with the sealing portion, and the connector is fartheraway from the sealing portion than the necked opening portion along anaxial direction of the anchoring portion in the presetting state, andwherein the connector is flush with the necked opening portion orfarther away from the sealing portion than the necked opening portionalong the axial direction of the anchoring portion in the abuttingstate.
 12. The left atrial appendage occluder for improving sealingeffect of claim 7, wherein the connector comprises an outer ring and aninner ring nested within the outer ring, and wherein one of the firstconverging part and the second converging part extends through and isfixed in the inner ring, and the other one of the first converging partand the second converging part extends through and is fixed in a gapbetween the inner ring and the outer ring.
 13. The left atrial appendageoccluder for improving sealing effect of claim 7, wherein the connectorcomprises an outer ring and an inner ring nested within the outer ring,and wherein one of the first converging part and the second convergingpart extends through and is fixed in a gap between the inner ring andthe outer ring, and the other one of the first converging part and thesecond converging part penetrates through the inner ring and is providedwith a retainer abutted against the connector, the retainer being fixedto one end of the inner ring where the other one of the first convergingpart and the second converging part extends out.
 14. The left atrialappendage occluder for improving sealing effect of claim 7, wherein theconnector comprises a body having two passages arranged side by side,and wherein the first converging part and the second converging partextend through the two passages respectively and are provided with tworetainers abutted against respective sides of the passages where thefirst converging part and the second converging part extend outcorrespondingly.
 15. The left atrial appendage occluder for improvingsealing effect of claim 1, wherein the sealing portion is a sealing discand is provided with a presetting state and an abutting state, andwherein in the presetting state the sealing portion is free from contactwith the anchoring portion, and wherein in the abutting state thesealing portion is in contact with the anchoring portion, and a middlepart of a disc bottom of the sealing disc in the abutting state isdeformed facing axially toward the anchoring portion with respect to thepresetting state.
 16. The left atrial appendage occluder for improvingsealing effect of claim 1, wherein: the sealing portion and theanchoring portion are formed individually and abut against each otherduring an assembling process; and after thermoforming the sealingportion and the anchoring portion are assembled together, and whereinthe sealing portion and the anchoring portion are in a first state in aninitial contact with each other during assembly, and wherein connectionparts of the sealing portion and the anchoring portion are in a secondstate after axially moving a predetermined distance toward each other.17. The left atrial appendage occluder for improving sealing effect ofclaim 16, wherein the connection parts of the sealing portion and theanchoring portion are respectively disposed at middle parts of thesealing portion and the anchoring portion in a radial direction, andwherein in the first state the sealing portion and the anchoring portionare in contact with each other at peripheral regions around theconnection parts respectively.
 18. The left atrial appendage occluderfor improving sealing effect of claim 17, wherein in the second state apart of the sealing portion connected with the anchoring portion movedtowards the anchoring portion with respect to the first state, and thepredetermined distance is defined according to one of: an axial force ofthe connection parts between the sealing portion and the anchoringportion; a pressing force at contacting parts of the sealing portion andthe anchoring portion; and a deformation of the part of the sealingportion connected with the anchoring portion.
 19. The left atrialappendage occluder for improving sealing effect of claim 18, wherein thedeformation is an axial displacement of a predetermined part of thesealing portion, or an angle between the predetermined part of thesealing portion and an axis of the sealing portion.
 20. A method formanufacturing a left atrial appendage occluder for improving sealingeffect of claim 1, comprising: performing thermoforming on the sealingportion and the anchoring portion; when assembling the sealing portionwith the anchoring portion, causing the sealing portion and theanchoring portion to move toward each other to reach a first state,wherein in the first state the sealing portion and the anchoring portionare in initial contact with each other; causing the sealing portion andthe anchoring portion to move axially toward each other a predetermineddistance to reach a second state; and fixing connection parts of thesealing portion and the anchoring portion together, wherein theconnection parts are maintained in the second state to completeassembly.